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Performance, Economics & Sustainability to Parking Garages

July, 2011

By Michael Naylor

Solid-state lighting systems using white-light LEDs are a viable solution for both covered and uncovered parking facilities as they begin to rival the performance of conventional lighting systems. This is good news for those who design, build and manage parking facilities and are interested in performance, economic and sustainability benefits.
A well-designed LED lighting system for parking facilities has multiple benefits compared with metal-halide and high-pressure sodium systems. Five key benefits are improving lighting performance, reducing maintenance time and costs, reducing energy costs, reducing a facility’s environmental footprint and integrating LEDs and controls.
1. Improved Performance: If LED lighting systems are designed properly, more than 90% of the light leaves the luminaire. This improves luminaire efficiency and efficacy, which, when paired with good optical design, increases lighting uniformity. Additionally, solid-state lighting luminaires are inherently less susceptible to temperature variations, vandalism, breakage, or damage from high winds and vibration.
2. Reduces Maintenance Time and Costs: With a minimum 50,000-hour lamp life, LED systems can easily last more than a decade before requiring replacement – greatly reducing maintenance costs associated with conventional lighting systems. As the time and labor traditionally dedicated to servicing lamps and ballasts are significantly reduced, facility management resources become available to focus on other tasks.
3. Reduces Energy Costs: LEDs are more energy efficient than metal-halide and high-pressure sodium systems and can have a significant impact on energy use and costs. In fact, the U.S. Department of Energy projects that between 2010 and 2030, LED lighting could save 1,488 terawatt hours – representing $120 billion in energy savings at today’s prices.
4. More Sustainable: LEDs are inherently more environmentally friendly, because they do not use mercury or other detrimental, potentially harmful materials. And because LED systems last much longer and consume much less energy than fluorescent lighting counterparts, Less waste is going to landfills and less coal is being burned in power generation. These environmental benefits can contribute significantly to the sustainability goals for new and existing parking facilities.
5. LED Benefits Increase With Controls: Unlike conventional light sources, the performance of LED systems significantly improves when controls are added. This makes LEDs excellent candidates to take advantage of occupancy sensors, dimming, or facility and campus-wide energy-management programs, which further enhance their overall cost-effectiveness.
Increasingly, the combination of digital LED lighting with digital lighting controls is making a more profound impact on the application and selection of LED systems for mainstream general lighting applications. As a general rule, LEDs are more “control-friendly” than conventional light sources commonly used today.
The LED light source features a true instant-on capability, and its life is not negatively impacted by frequent on/off switching cycles, making it ideal for motion-sensing applications. Dimming LEDs actually improves their efficiency and extends their service life, while maintaining a more constant color temperature through the dimming range than other sources, which allows more advanced control options to be easily incorporated.
These combined capabilities allow digital controls to substantially leverage LED performance – lengthening LED life expectancy and improving system efficacy – making the overall economic equation more attractive.
Beyond capability, the inherent compatibility of LEDs with digital lighting controls may ultimately hold the greatest potential for economic benefit. With properly designed driver and control components, LEDs can be the core component in digital light engines that interface directly with discrete control devices on-board every light fixture.
The result is an “intelligent” light fixture that has the ability to monitor and respond to its environment, and to perform pre-programmed tasks to further conserve input power and reduce lighting maintenance.
One example of such a task is executing a constant lumen output over system life to eliminate the waste of over-lighting associated with initial lumens delivered early in a lighting installation. Other potential tasks include monitor and adapt to variations in ambient temperature; monitor system life; and detect a fault in the system for quicker troubleshooting and maintenance.
Given the significant advantages of advanced digital lighting technologies, LED lighting is quickly becoming the innovation of choice for commercial building engineers and parking facility managers across North America for facilities seeking long-term sustainable solutions for saving energy, reducing maintenance and operating costs, and minimizing their environmental impact.
Michael Naylor is Acuity Brands Lighting Vice President and General Manager, Outdoor Products. He can be reached at michael.naylor@acuitybrands.com

Sidebar:
Mall of America to Begin Largest U.S. LED Lighting Parking Ramp Project
Mall of America, the nation’s largest retail and entertainment complex, will be making the conversion from traditional to LED lighting in its two parking decks – totaling 3.9 million square feet – to reduce energy and achieve sustainability goals.
Starting in July 2011, the complex, located in Bloomington, MN, will begin replacing its 5,400 metal-halide and high-pressure sodium fixtures with LED luminaires from Acuity Brands LED Outdoor’s Park and Walk portfolios – Terson Ratio PG, Terson Ratio 4.0 and Lithonia Lighting ALXW.
“To continue with our dedication to being environmentally responsible, we are thrilled to announce a project of this magnitude,” said Rich Hoge, Director of Technical Operations for Mall of America. “It is incredible to be able to reduce our parking ramp energy demand by two-thirds or in excess of an 800KW demand reduction.”
This conversion project, the largest of its kind in the U.S., is designed to reduce energy consumption in the ramps by 66%. The energy saved would be enough to power more than 11,000 homes for a year.
The project is slated to be completed by early fall 2011.


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